I also have a 835 and went through 7 chokes and handfulls of different ammo to get the gun to pattern the way i wanted it. I even sent the barrel back to mossberg thinking it was tweaked or something. All my shooting pattern were open in the middle and was real mind boggling. I shoot 3 1/2 Federals 5 shot. Im actually thinking of getting a new gun because it still has a opening in the middle of my shots.